diff --git a/mm/mmap.c b/mm/mmap.c
index 6b7b1a9..2b43fa1 100644
--- a/mm/mmap.c
+++ b/mm/mmap.c
@@ -87,6 +87,9 @@
 int sysctl_max_map_count __read_mostly = DEFAULT_MAX_MAP_COUNT;
 struct percpu_counter vm_committed_as;
 
+/* amount of vm to protect from userspace access */
+unsigned long mmap_min_addr = CONFIG_DEFAULT_MMAP_MIN_ADDR;
+
 /*
  * Check that a process has enough memory to allocate a new virtual
  * mapping. 0 means there is enough memory for the allocation to